Ash consists of the metal oxides and heavier elements that remain after combustion removes the organic, gaseous and volatile components. Coal quality and pricing in part depends on sulfur, chlorine and ash content of the coal, and these parameters also indicate the origin and type of coal as well as combustion properties in the furnace, kiln or boiler. EDXRF offers a fast and simple low cost method of measuring the sulfur and chlorine content and predicting the % ash content, without the need for radioisotopes or long combustion analytical methods. To demonstrate repeatability, five calibration standards were selected to show the lower and higher levels of S, Cl and % ash concentration ranges. Each was measured in 10 repeat analyses using an analysis time of 300 sec per sample without moving the sample between measurements to determine and average value for precision. If desired, repeatability can be enhanced by using longer measurement times.